double whistle and 2 different calls...

[M&M Guy]

I have to agree with JRut - since this was a non-important call (in the grand scheme of things), I would defer to the official who is most insistent. I'm not sure I would automatically defer to them just because they were a senior official, but because we look better as a crew not standing on the floor arguing amongst ourselves. But I would certainly have that discussion at halftime, or after the game, as to why my partner would be making such a call in my area. Perhaps it really was in the "gray area" JRut mentions. Perhaps you were too close to the play and didn't see it like everyone else in the gym. Or, perhaps, my partner was (in their mind) trying too hard to help out a less-experienced partner. But spend as little time as possible discussing the call on the floor - pick one and go with it. Then see if that can be avoided in the future.